M9 Field Protective Mask
|period = 1947-1995 |issued = Military |filter = M11 |caption = A typical example of an M9A1 Field Protective Mask with ABC-M4 Hood (In Pouch) and M5A1 Protective Ointment Kit.|previous = M5-11-7 Combat Service Mask, M8-11-10 Snout-Type Service Mask|prototype = |thread = 60mm|manufacturer = Daytona Rubber, Firestone Tire & Rubber Co, Various Others}} The M9 Series Field Protective Masks are some of the most successful gas masks to be used by the United States military, derivations being adopted by at least six other countries. Starting production around 1947, the M9 Series remained in standard infantry service until the early 1960s, when it was phased out with the introduction of the M17 Field Protective Mask. Despite being replaced as a standard infantry mask by the M17 Series during the early/mid Vietnam War, the M9 series continued service with National Guardsmen and Law Enforcement (even though they had specialty gas masks of their own) during protests against the war. It was also issued to Civilian Defence workers and civilians alike, and the M9 series would be used by these organizations up until the 1970s. Even after the M9 series was phased out by general infantry, policemen and civilians alike, it continued its use by the U.S. Heavy Decontamination Crews, Chemical Stockpile Inspectors and Handlers, and EOD Personnel used the mask from its conception in the late 1940s until the early 1990s as a part of the ABC-M21 Rocket Propellant, M15 Compressed Air Breathing, Toxicological Agents Protective (T.A.P.) Gear ensembles. Development By late 1944, the U.S. military had multiple standard service masks in use, including, but not limited to - the M3/M3A1 and M4/M4A1 Lightweight Service Masks, and the M5 Combat Service Mask. It was justifiably decided that the M3/M4 Lightweight Service Masks were too bulky in comparison to the M5 Mask and that the full adoption of an "Assault-Type" service mask would be the best possible outcome, however the complications in mass-producing the M5 and its poor handling of below-zero climates lead the CWS into investigating alternative manufacturing methods and designs to replace the M5. Suspecting a full-scale invasion of the Japanese home islands was imminent, the first step taken towards supplying the Pacific Theater of Operations with "Assault" Masks was the M8-11-10 Snout-Type Service Mask. The M8 was little more than a standard M3 or M4 Series Lightweight Facepiece with an upgraded C4 Head Harness and a metal angled 60mm thread assembly attached to the stem the M3 Hose had previously occupied, and served as a stop-gap design to issue while development continued on improving a new side-canister mask. The CWS Division at the Massachusetts Institute of Technology, which had previously developed the M5-11-7, was now dealing not only with how to improve the means of effectively molding a side-canister mask, but also to produce them of a suitable artificial rubber which was as resistant to extreme temperatures as it was to chemical agents. One of the first developments which began to show promise was a drastic modification to the M3 Faceblank design, which had a deflector channel that ran over the nose pocket, rather than cutting into the pre-existing vertical deflectors. In addition, experiments were made to produce M5 and M8 Masks from Butyl, a new type of artificial rubber which both had a strong resistance to all known chemical warfare agents as well as to temperatures. Butyl had been chosen as a prime candidate as a rubber compound for gas mask facepieces as early as 1943, but limited availability and production of butyl rubber heavily set back development and thus neoprene still was widely used instead up until this point, where improved blends and molding techniques were developed. By 1945, the final prototype was designated the E19R25 (Experiment 19, Revision 25). MIT-E19R25-M11 Combat Service Mask The mask which had been developed had a solid injection-molded faceblank utilizing an improved blend of black neoprene rubber, a C15 Outlet Valve, and a 60mm threaded filter inlet for the M11 Combat Canister. Like the M5-11-7 Combat Service Mask, this thread assembly attached to an port on the side of the face piece, however unlike the M5, this port was molded as a part of the faceblank as one piece, leading to the molded-in "mustache-type" airflow deflector channels, which wrapped over the 'nose pocket' of the faceblank and ended under each eyepiece. This gave the mask a rather humorous appearance of having a large, comical-looking nose while also being much more effective at clarifying the lenses and faceblank production. Inside the mask, there was an oronasal cup, which was improved over the types used on the M3 and M4 Series Lightweight Masks. This was because the E19R25's oronasal cup curled in, as opposed to curling out, which gave it a better seal. The mask also utilized new, improved laminated glass eyepieces (MIT-E2) with thicker aluminum eyerings (MIT-E1R10) over the older steel-framed, cellulose acetate eyepieces. Like the older M5 Combat Service Mask, the MIT-E19R25 used the C4 Head Harness Assembly, which included a nape strap to support the canister. There were two main facepiece variants of the E19R25 - the E19R25 and the E19R25-F (Featherweight). The main difference is the carriers issued and minor construction details on the inlet valve. The E19R25 was issued with the MIT-E19R2 Combat Carrier, a compact, boxy OD cotton duck canvas bag with a roll-flap closure and an extended indent in the profile to accommodate the canister. The E19R25-F was issued with the MIT-E20 Combat Carrier, and even smaller, rectangular pouch which was supplied with the standard M1910 Wire Hook Hanger on the back to suspend the carrier from the cartridge belt. In addition, the kit also had a water-resistant inlet valve, weatherproofed M11 Canister, and a canister waterproofing plug kit and instruction card. image18.jpg|The three carriers approved for the E19R25 Series. image20.jpg|Much of the Same. image21.jpg|Much of the Same. image50.jpg|Carriers as Worn. image15.jpg|Differences between the E19R25 and E19R25-F Facepieces. image16.jpg|The MIT-E19R25-M11-E20 Featherweight Combat Service Mask. MIT-E19R2 Combat Service Carrier The main carrier assembly issued to the MIT-E19R25 was the MIT-E19R2 Combat Carrier, noted by its construction of water-resistant OD cotton dock, lopsided shape to accommodate the M11 Combat Canister on the mask, and its roll-flap closure system, which was fastened by two 'Lift-The-Dot' Fasteners, as stated previously. The carrier also featured removable carry straps and internal pockets for the Anti-Dim Stock or Cloth, the M1 Eyeshields, M5 Protective Ointment, and two Individual Gas Protective Covers. The E19R2 Combat Carrier was noted for its convenience and how it allowed the quickest donning times of the mask when compared to the E20 and M7A1 Carriers, however, it was noticed that soldiers would often incorrectly roll the carrier opening gusset closed, and that the accessory pockets often interfered with removing and replacing the mask. With the addition of snap fasteners to the inner accessory pockets, the speed of removing helmet, removing mask from carrier, donning, clearing, sealing, fastening nape strap, replacing helmet and closing the carrier was increased from 23.0 seconds without snap fasteners to 19.7 seconds with. However, it was found that the E19R2 Carriers caused the facepieces to take on a permanent set cease near the chinpiece during long storage periods, and generally had very poor water resistance, with all tests proving that the carriers would become flooded when immersed no mater how tightly the roll. Reports state that a longer roll-flap closure similar to the M7/M7A1 Carriers were being researched. MIT-E20 Featherweight Combat Service Carrier The carrier bag issued with the MIT-E19R25-F Mask was the MIT-E20, a small, rectangular carrier made of OD103 Canvas Duck Fabric with a single flap closure at the top, fastened with 2 'Lift-The-Dot' Fasteners, and removable carry straps, similar to the E19R2 Carrier. Unlike the E19R2, the E20 Carrier had an M1910 Wire Hook to suspend the carrier from the user's cartridge belt, and no internal accommodations for the Individual Gas Covers, Eyeshields, or Protective Ointment. The only internal pocket was a small sleeve on the lid for the anti-Dim cloth. Additionally, the mask had to be stored inside with the canister removed and sealed with the waterproofing plug set issued to the E19R25-F Kit, quite reminiscent of how the British Light Anti-Gas Respirators were stored. Due to this, the E19R25-F Masks had the slowest drill time (35.2 seconds), due to being stored with the filter plugged and unscrewed from the facepiece. These extra steps also required additional drill procedures to tore the mask in 'alert' or 'sealed' configurations. The E20 Carrier also had absolutely no waterproof capabilities, needless to say, and tests showed that even in rainy conditions, it was not uncommon for the E20 Carrier to become flooded. Despite the highly-praised, extreme light weight of the E19R25-F Gas Mask, its concept was ultimately deemed unsatisfactory due to inconvenience in donning and lack of accessories. The MIT-E20 Carrier would cease development shortly after. M7/M7A1 Combat Service Carrier The M7A1 Combat Service Carrier is little more than a slight modification to the M7 Carrier used with the M5-11-7 Army Combat Service Mask. It is a large, semi-hexagonal carrier made of cotton duck canvas coated on both sides with black butyl rubber. The side opening is secured with a roll flap and a row of 3 'Lift-The-Dot' Fasteners. The main and only difference between the M7 and M7A1 is that the former has its straps permanently sewn on to the carrier body, whereas the M7A1 is supplied with 4 grommets to allow removal of the straps via standard snap-hooks. Improvements to the butyl coating made the M7A1 less reflective as well, when compared to the standard M7 Carrier. The M7A1 Carrier was appreciated for its roominess and its totally waterproof design, more than capable of holding the E19R25 Mask, with attached M11 Canister, and all authorized accessories. The time needed to don the mask was, however, slow (31.5 seconds for the M7A1, and 25.6 seconds for the M7) due to the rolled opening gusset taking up time, and additionally, the non-reflective butyl used on the M7A1 was tackier than the shiny rubber coating used on the M7, owing to greater friction as the mask was pulled out. The carrier was also disadvantageous for its great size when compared to the E19R2 and especially E20 Carriers, and reports showed that men preferred the M7/M7A1 Carriers the least in all situations. Additional problems also included cases where the rubber coating was susceptible to wearing away from field abrasion, and complaints of the snap-hook and grommet removable carry straps were inconvenient to fasten. Nevertheless, reports concluded that the original M7 Carrier was the best of all carrier designs trialed for the E19R25 and E19R25-F Masks, and work began on improving the materials and construction of the M7 Bag to correct the previously noted flaws. C48R1 Field Protective Mask The E19R25 was noted for it's great improvement in comfort, durability, range of visibility, and better handling in colder temperatures, and so sometime between 1945 and 1947, the MIT-E19R25-M11-M7 Combat Service Mask was reworked and finalized as the C48R1 Field Protective Mask for additional field testing. The C48R1 Mask was not very different from the E19R25, as they both used the same molds, same black neoprene rubber, same laminated glass and aluminum eyepieces, and same inner oronasal cup. The main and only changes to the facepieces were that the C15 Valves used on the C48R1 eliminated the sleeve extension behind the rubber shroud, and later variants included a pull tab for easy removal in arctic weather. Another change that took place was upgrading the earlier C4 Head Harness was upgraded to the newer C8. The C8 head harness had a rectangular head pad made of thick, grey (later black) cotton duck fabric, similar to the MIIA1 Harness, as opposed to the black or sage green triangular vinyl fabric head pad of the WWII C4 Harness. Like it's cousin harness, the C4, the C8 also utilized a nape strap that was intended to prevent the weight of the canister from shifting the mask on the face. C15R1 Carrier The C15R1 Carrier, which was remarkably similar to the M7 Carrier, was the approved carrier design issued with the C48R1. It followed the same design pattern and relatively the same dimensions as the older M7 except that the C15R1 was made of olive drab cotton duck fabric which was rubberized on the inside, as opposed to being completely rubberized canvas like the M7. M9 Field Protective Mask Later on, the C48R1 was standardized as the M9 Gas Mask. It was exactly the same as the C48R1 in every way, except the M9 used a faceblank of white natural-artificial rubber blend, instead of black neoprene like the C48R1. The M9 Gas Mask was also later updated as the M9A1 Field Protective Mask sometime in the early 1950's. The mask's face piece and accessories were exactly the same as the M9, but the carrier instead, was updated. It was changed from a large, bulky, waterproof C15R1 Carrier, to a small, rectangular, non-waterproof M11 Carrier. The air-tight, vacuum-sealed tins the masks were issued in underwent a change as well - M9 tins, which were originally labeled "MASK, GAS, M9", had that marking brushed over with green paint, and were stamped over with "MASK PROTECTIVE, FIELD, M9A1". Each M9/M9A1 came issued with an M9 Facepiece (with faceform tied in place), M11 Service Canister (tied to the back of the faceform), an C15R1/M7A1 (M9) or M11 (M9) carrier (had the mask stuffed inside) and an Anti-Fog Cloth in its Tin. Accessories M4 Chemical Hood: '''A rubberized nylon hood that covers all of the mask except the lenses and the filter opening. The hood has an olive drab nylon cord around the neck, which is threaded through a plastic plate to close the hood for a better seal. Versions of this hood were also made for the M8-11-10 Snout Type Mask and M3 and M4 Lightweight Service Masks. '''MI Waterproofing Bag (issued with the M9A1 during the Vietnam War and after): A plastic bag with rubber bands inside it on a cardboard sleeve meant to seal the bag with the mask inside to waterproof it when crossing rivers and streams, for the M11 Carrier was not waterproofed like the earlier C15R1 Carrier. Optical Inserts: '''A special pair of glasses with frames that loop around the inside of the lenses. Meant for soldiers with vision defects. '''M3 T.A.P. Hood: Similar to the M4 Hood, but made of a thicker rubberized material with a second layer. Used for heavy decontamination and other similar tasks. M1 Winterization Kit: A rubberized fabric cover that helps the mask's rubber from becoming stiff in extreme cold. Covers everything but the lenses, "nose", and filter inlet and also acts as a chemical hood. Foreign Variants and Users Italy: '''The M9A1 was adopted and used by the Italian army. '''Finland: M/61 - made of grey rubber, and manufactured by Nokia with three different models: * Model 1 - Most similar to the U.S. M9. The only changes were the addition of a Nokia manufacture mark on the filter side, and 'SA' (Finnish: Suomen Asevoimat "Finnish Military") replacing 'US' at the top. * Model 2 - This version has a longer outlet valve cover, and a peripheral seal was added. The 'SA' marking was removed, and the watchtower of the Finnish defence forces was added on the opposite side to the filter. * Model 3 - Final, most common model. The rubber exhalation assembly was replaced by a black plastic assembly, incorporating a voice diaphragm, the cover featuring the distinctive watchtower of the Finnish defence forces. Sweden: Skyddsmask 51 - Similar in appearance to the M9A1, made of dark green rubber, has a similar outlet valve cover to the second model M/61. Fairly common. Japan: Type 2 Protective Mask - A fairly distant, but somewhat similar copy of the M9/M9A1. Made of light olive drab rubber, lenses are more rounded, the outlet valve is made entirely of metal. These masks are very rare outside Japan. South Korea: KM9A1 - Made of black rubber, similar once again to the E48. Very rare, but somewhat more common than the Japanese type. Often found as specimens issued to Iraq and other forces in the Middle East - these are commonly mislabeled as 'Bulgarian' M9 copies due to the rough assumption myth started by Bart Wilkus because of the OM-10 clone produced by the same country. There is no logical evidence these are Bulgarian-made as they feature the same construction as the KM9A1, share no hardware or design patterns coexisting with period Bulgarian mask designs, and Iraq was commonly issued South Korean-produced equipment. Yugoslavia/Serbia: M1/M2 Series - Made of an aqua-ish green rubber, the M1 had a similar carrier bag to the M11, and was the military counterpart of the MC-1, which had no oral-nasal cup, had "MC-1" stamped on the left side of the mask in black, also had a cheaper carrier. M2: made of the same color rubber, the M2 basically was an update of the M1. It had black plastic frames instead of the green metal of the M1. A variant called the MC-2 had a drinking feature. The M2 had two different types of outlet valves - one that was a plastic cage, and one with a green deflector. A model called the M2-F was made of all black rubber and had black parts, and resembled the Finnish Nokia M/61 (third model), for it had a similar outlet vallve/voice diaphragm assembly. Egypt: M2 - Licensed exact copy of the Yugoslavian M2. Iraq: Uses the KM9A1 and the Yugoslavian M1 (renamed the M-65). Additional Notes The M9/M9A1 had many strange issues and problems with the rubber, such as the white rubber had a tendency to discolor a dark olive drab green if not taken care of properly. Badly discolored M9s can be confused for the Swedish Skyddsmaske 51, or the other way around. The easiest way to tell the difference is the forehead markings - an M9 will have a "US" mark. Skyddsmaske 51s also have longer outlet valve covers. Both the M9 and M9A1 were made in both right and left-handed models. The right-handed model has the canister on the left side of the face piece and is the most commonly found. Left-handed versions had the canister on the right side of the face piece, for they were needed less, and thus, less were made. Category:Vietnam Era Masks Category:Cold War Era Mask Category:Full Face Masks Category:Military Gas Masks Category:United States Category:Italy